SFI 25.5 Chassis Certification
#1
SFI 25.5 Chassis Certification
Hello everyone, first of all I'm new to the site and my name is Don. I have an 86 camaro that currently runs in the mid 10's with a torque arm suspension and no power adder. I am upgrading this winter to a 25.5 certification and was wondering if anyone has any photos of or any words of wisdom as far as placement of the floor bars. Should I take the time to cut the floor out and cut it into pieces and weld it back to the bars, or should I cut notches in the floor and run the bars then weld them together, or should I run the bars under the floor? What has worked for most people the best? I am staying with mild steel as I cannot afford or weld 4130 chromoly, and am afraid of the brittle nature. The car will also be equiped with a four link in the rear. Thanks for any help. If you'd like to know anything else just ask. http://www.momsracing.com/07/10-21-2.../101B5370.html
#2
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From: Boosted Land
Car: 92 Z28
Engine: Boosted LSX
Re: SFI 25.5 Chassis Certification
DON !!! look what the cat dragged in.. Your not gonna find anybody on this site with a 25.5 man.
shoot me a e-mail I have TONS of pic's and can get you more if needed.
BTW this is Chris from sunset.
shoot me a e-mail I have TONS of pic's and can get you more if needed.
BTW this is Chris from sunset.
#3
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: SFI 25.5 Chassis Certification
I don't even have a spec chassis. I don't need one. I don't even need a chassis certification until 8.99 under IHRA rules but I do have a full cage in the car.
You can buy the spec plans directly from SFI for $35. You won't find any free information anywhere on the web about chassis SFI specs. You don't need a 25.5 spec unless the car will run 7.50 to 8.49. If you are going to run that fast, have the chassis professionally built by a chassis shop who already knows what needs to be done.
http://www.sfifoundation.com/
Looks like you have a lot of body roll. Install a rear anti-roll bar to fix that.
You can buy the spec plans directly from SFI for $35. You won't find any free information anywhere on the web about chassis SFI specs. You don't need a 25.5 spec unless the car will run 7.50 to 8.49. If you are going to run that fast, have the chassis professionally built by a chassis shop who already knows what needs to be done.
http://www.sfifoundation.com/
Looks like you have a lot of body roll. Install a rear anti-roll bar to fix that.
#4
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From: Boosted Land
Car: 92 Z28
Engine: Boosted LSX
Re: SFI 25.5 Chassis Certification
He will go 8.49 + with in the next year 1/2.
I know his car and his Dads car. His Dad is already knockin on the 7's doors.
Ive got the files he needs just gotta dig em out and e-mail em on ever to him.
I know his car and his Dads car. His Dad is already knockin on the 7's doors.
Ive got the files he needs just gotta dig em out and e-mail em on ever to him.
#5
Re: SFI 25.5 Chassis Certification
The car will go that fast within 2 years. I'm in college right now, so I can't afford to have a chassis shop do the work. We do everything ourselves, and it's always been that way. Dad has a ladder bar setup that has gone 8.12 @ 174 mph and has had some success in Outlaw 10.5. I understand that the specs need purchased, I'm getting them here in the next week or 2. I was just wondering if anyone has suggestions on whether to run the floor bars in the car, in the floor, under the floor or what? I'm not asking for specs, I've already done that research. Dad got into the wall this last weekend, so I want to build my car safer for when I get some more power. He was very fortunate that it happened at the 1/8 mile and he walked away. I want a chassis that will handle anything, and we're do it yourselfers...
#6
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Joined: Jul 1999
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: SFI 25.5 Chassis Certification
#7
Re: SFI 25.5 Chassis Certification
That's why I stopped by to see if anyone had any ideas or has a 3rd generation f body that is 25.5 certified. I have a pretty good idea of what I'm gonna do with it, just wondering if anyone has done this, and what has worked best for them. I'm not trying to steal specs or anything. I'm a 21 year old college student who bought a car in the junkyard a year and a half ago, and have fixed it up, raced 2 seasons (one with a sbc, one with a bbc), and I'm ready to do the next step since I'm graduating in the spring. I'll have more money to put into it, and some more time to improve on what I've already built. Trust me, I built the car long before I got on any message boards and asked for advice. I can do it without asking questions no problem, just wondering if anyone has any thoughts to share on it. I drive home from school 3 hrs on friday to work on the car all weekend, and drive 3 hrs to school monday morning to go to class at 8 am. Like I said, my dad has an 82 that is very competitive in the area in alot of heads up classes. I'm just trying to gain some insight. Nothing more. I'm not gonna be talked out of doing the 25.5 at this point. The car will need it someday, and after dad tagged the wall last weekend in his car, I'm ready to upgrade from the 10pt cage I have now in my car.
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#8
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From: Boosted Land
Car: 92 Z28
Engine: Boosted LSX
Re: SFI 25.5 Chassis Certification
good pic's I have for ya or anyone else who wants em.
http://www.cecoatings.com/images/oth...production.jpg
http://www.cecoatings.com/images/oth...0HZqEod_ph.jpg
http://www.cecoatings.com/images/oth...n/000_0050.jpg
http://www.cecoatings.com/images/oth...%20(Large).jpg
http://www.cecoatings.com/images/oth...20(Medium).jpg
http://www.cecoatings.com/images/oth...production.jpg
http://www.cecoatings.com/images/oth...0HZqEod_ph.jpg
http://www.cecoatings.com/images/oth...n/000_0050.jpg
http://www.cecoatings.com/images/oth...%20(Large).jpg
http://www.cecoatings.com/images/oth...20(Medium).jpg
#9
Re: SFI 25.5 Chassis Certification
Thanks Chris. You have any pics of people doing the 25.5 with the factory front frame stubs, instead of the tube front end? Like pics of the floor near the transmission tunnel?
#10
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From: Boosted Land
Car: 92 Z28
Engine: Boosted LSX
Re: SFI 25.5 Chassis Certification
I'll look and see. if I do not up on my server. Maybe on my laptop. if so I'll upload em and let ya know. most 25.5 cars won't have factory rails still.
#13
Re: SFI 25.5 Chassis Certification
Yeah, Norwalk's Outlaw Street and stuff like that...thank goodness he left all the stuff in there though and just left that program...the incident with the wall would've been alot worse.
#14
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From: Aloha, Oregon
Car: '91 Camaro Z28, '85 Camaro Z28
Engine: LB9, LB9
Transmission: T5, 700r4
Axle/Gears: Eaton 3.73 Posi, 3.23 Posi
Re: SFI 25.5 Chassis Certification
you could always ask here:
Drag Coverage
some of the guys there are running Pro Mods so I'm sure somebody could help you out.
Drag Coverage
some of the guys there are running Pro Mods so I'm sure somebody could help you out.
#16
#17
Re: SFI 25.5 Chassis Certification
Okay, thank you, I appreciate it....like I said, I'm looking for ideas to help make this a nice install...I could do it today if I wanted, just want to make sure I do it right the first time...
#18
Re: SFI 25.5 Chassis Certification
the rules for the class you want to run have just as much to do with the answer as the sfi does, some sanctioning bodies say factory floor pan, some say frame rails to the back of door can be altered et. so without knowing the rules of the class you want to run its really hard to suggest anything. if the rules allowed it cut the rails off at the firewall so you can put exhaust in easier, but very few classes allow that so f-body's get screwed and fox body's get away with it, good luck with the build.
#19
Re: SFI 25.5 Chassis Certification
oh and by the way i agree that safety should come before the power, so i think you are doing the right thing. i see alot of people say you dont need it, but is there such thing as too safe? some of the sanctioning bodies have silly rules that sometimes comprimise safety, i sort of see the reason but i would think safety would be paramount. so bottom line build the safest car you can, then go have fun with it
#20
Re: SFI 25.5 Chassis Certification
More sage advice has never been given. In retrospect, it's still a very good day when you can walk away from the car with only a bruise in your wallet after having tangled with the barriers or having done something needing ailerons.
#21
Re: SFI 25.5 Chassis Certification
Well, I was home from school for the weekend and got to looking some things over. I determined that it's too much of a pain to get the car certified to 7.5, it's good to 8.50 now. So I'm going to just add some more pipes to the cage around me and make it safer in my mind. When I decide to go faster than that I'll start with a fresh car. I don't know if I'm going to backhalf the car now or not. I'm running true 10.5's with little trouble, so I may just switch to a ladder bar setup so the car comes out of the hole better. I keep changing my mind though. It'd be easier if I didn't go to school 3 hours from home and have to drive 6 hrs every weekend to work on it. The off season just started, so I've got plenty of time to decide.
#22
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: SFI 25.5 Chassis Certification
Although I don't need it, I may add the funny car tubes to my cage this winter.
#23
Re: SFI 25.5 Chassis Certification
I'm considering that as well. I'm going to add the x's to my doors, and maybe the funny car cage. I'm probably going to backhalf the car and just add the necessary cage to support it, and leave it alone at that. It's too much work to change my existing cage to a 25.5 at the moment, and with school I don't have the time to do it right. I'm just going to go the cheaper route and upgrade what I already have.
#24
Re: SFI 25.5 Chassis Certification
first more tubes in the right places can help, so can properly placed gussets. how about the rest of the safety gear? also i dont know if you really need to go to ladder bars, i dont know how much hp you have now but in my camaro i still have a torque arm (random technology) and i just set a new personal best 60 ft and it was with 3 thousandths all day, i pulled a 1.28 60 ft, on the rears lol sets the front tires down at 80 to 90 ft im guessing, i should have a video soon. the biggest thing is a huge anti roll bar to keep the chassis level, i thought i would be able to stop dragging the bumper with just the front limiters, i was wrong. i still had to lower the nitrous start percent its at 20 percent running a 225 shot puts out close to 900 hp all out ran a 5.78 1/8 mile. so the stock suspension can work good and consistant, i dont know what hp you are going to get up over the winter but bmr i think makes a shorter torque arm it is probably a good idea if you are going to shoot for 8's
i can see you dont have an anti roll bar, so i reccommend one i built mine so i cant rec. anybodys in particular but bmr makes a drag bar or something like that, its kinda pricey and the mounting points are questionable but the say they have customers in the 1.30's i think s and w makes a more drastic type that needs parts welded in over the axle and i dont know if you can use a factory tank with it. i built mine so it is right under the cage plates and i plated both the floor and frame rails before i put the crossmember in for it, i also built a fuel cell (i had a tig welder and a sheet of aluminum and a shear and a brake so i built it) cuse i wanted it to fit and to have a fuel gauge, im greedy i guess. also i dont know what you have in the car but door x bars will stiffen up things a bit and be safer, also an x bar in the roof helps to stiffen the car too, i am guessing there is an x in the rear down tubes already, if there isnt put one. the roof x or diagonal is also very important if ever there is an impact on the roof weather it be a wall or a car nose (stranger things have happened). also seat mounting and belt mounting are important, and related to that is switch placement i have seen alot of cars where the driver cant reach the switches when strapped in, so that leads to the belts being loose so they can just flip the switch, then they make a lap with the belts loose, not a good scenario. as far as the ride 8's are pretty fun and its even more fun if you can put on a show when you are fooling around and carry the front wheels about 80 ft
i can see you dont have an anti roll bar, so i reccommend one i built mine so i cant rec. anybodys in particular but bmr makes a drag bar or something like that, its kinda pricey and the mounting points are questionable but the say they have customers in the 1.30's i think s and w makes a more drastic type that needs parts welded in over the axle and i dont know if you can use a factory tank with it. i built mine so it is right under the cage plates and i plated both the floor and frame rails before i put the crossmember in for it, i also built a fuel cell (i had a tig welder and a sheet of aluminum and a shear and a brake so i built it) cuse i wanted it to fit and to have a fuel gauge, im greedy i guess. also i dont know what you have in the car but door x bars will stiffen up things a bit and be safer, also an x bar in the roof helps to stiffen the car too, i am guessing there is an x in the rear down tubes already, if there isnt put one. the roof x or diagonal is also very important if ever there is an impact on the roof weather it be a wall or a car nose (stranger things have happened). also seat mounting and belt mounting are important, and related to that is switch placement i have seen alot of cars where the driver cant reach the switches when strapped in, so that leads to the belts being loose so they can just flip the switch, then they make a lap with the belts loose, not a good scenario. as far as the ride 8's are pretty fun and its even more fun if you can put on a show when you are fooling around and carry the front wheels about 80 ft
#25
Re: SFI 25.5 Chassis Certification
The car isn't going to see 8's this year I'm afraid. Still have a year of school left and funds are getting tight. We have a machine shop and I've made a torque arm that is about 8" shorter than stock and mounted it to the transmission tunnel. I'm running stock coils in the back and an air shock with 30 lbs per side in the rear. The front is all stock v-6 springs and struts, so it's getting tired as well. I have a 468 bbc in it now that isn't making a terrible amount of power. Went a best of 10.52 at 129 mph this summer with a 60' in the 1.5's all year. I'm still running a th350 tansmission (th400 being built now with a brake) and foot breaking the car. Has a 9" BTE converter and 9" rear with 4.30's in it (had 3.89's and it made no difference).
I was going to cut it all up this winter and get the chassis certified farther, but I won't be that fast until the certification is up, so I'm just going to add some structural strength to the cage that I currently have. I mean I pulled the car from the junkyard just over a year and a half ago, so it's not that old to me and it's on its second drive train.
I was going to cut it all up this winter and get the chassis certified farther, but I won't be that fast until the certification is up, so I'm just going to add some structural strength to the cage that I currently have. I mean I pulled the car from the junkyard just over a year and a half ago, so it's not that old to me and it's on its second drive train.
Last edited by Little Z28; 10-28-2007 at 10:42 PM.
#26
Re: SFI 25.5 Chassis Certification
Oh, almost forgot....for anyone who saw the Pinks All Out from Budds Creek Maryland this summer...was in the beginning of June, and aired in late August....I have the gray camaro that got tossed in the second round cause they thought I was sandbagging...
#27
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From: Boosted Land
Car: 92 Z28
Engine: Boosted LSX
Re: SFI 25.5 Chassis Certification
Don,
I say toss in the Th400, do a 4link and coil overs on the 9inch and put some tubbs in it for now. Along with adding the extra bars to the cage this winter.
I forget but arnt you running your stock k-member/arms? Lighten it up a little with A tubular one like your dad got off me. and some tubular A arms. (ive got some of them Im not using if wanted)
I say toss in the Th400, do a 4link and coil overs on the 9inch and put some tubbs in it for now. Along with adding the extra bars to the cage this winter.
I forget but arnt you running your stock k-member/arms? Lighten it up a little with A tubular one like your dad got off me. and some tubular A arms. (ive got some of them Im not using if wanted)
#28
Re: SFI 25.5 Chassis Certification
The th400 is being built as we speak...I'm debating on a ladder bar or 4 link still...the cage is getting beefed up...car is doing on a diet...I'm looking for a k member and a arms to put in it here...new paint job in the spring again...
#30
Re: SFI 25.5 Chassis Certification
moroso trick springs in front would transfer a little better, spa1's would help too, do you have traction problems? do you really need to put ladder bars in it that make for a short instant center that isnt that adjustable and last but not least a good 4 link not a chicken spit comp engineering one is pretty expensive and you arent really making tons of hp so you could put that money (and time ) twords lighter pieces and that will make the car faster and more consistant the 400 may hurt a little in that it uses more power and 1st gear isnt as good, still better for a heavier car than a glide i am testing to see what a 350 holds up to since i am running one with a brake 5k stall and @900 hp. with an anti roll bar the torque arm is esentially a really long ladder bar, and since you run 1/4 mile the longer ic isnt a bad thing it wont unload the rears as easy down track. from the pics you are twisting the car up and wasteing power stiffen it up and use what you have better
when you made the torque arm did you attach it about where the original was hight wise ( i see its shorter) the hight of the attachment point is what will dictate you anti squat percenage also do you have lowere control arm reloacators in the rear? unless those springs are wasted i dont see why you need 30 psi in the bags out back
also you might want to consider a mid plate or even better mid and front plates the mid plate will apply the torque farther back on the chassis to make it easier to control the twist
when you made the torque arm did you attach it about where the original was hight wise ( i see its shorter) the hight of the attachment point is what will dictate you anti squat percenage also do you have lowere control arm reloacators in the rear? unless those springs are wasted i dont see why you need 30 psi in the bags out back
also you might want to consider a mid plate or even better mid and front plates the mid plate will apply the torque farther back on the chassis to make it easier to control the twist
Last edited by car_fixer; 10-28-2007 at 11:33 PM. Reason: more ideas
#31
Re: SFI 25.5 Chassis Certification
got a few pics of my car if you would like to see some things i did, i do need to do more though, and i will need the cage certified too hoping to add the 2 bars i need for certification soon
#32
Re: SFI 25.5 Chassis Certification
Anyone know off hand what a stock k member weighs? And what a stock a-arm goes per side? I'd like to change all that stuff out, but it's kinda pricey...and it's impossible to find used stuff...
#33
Re: SFI 25.5 Chassis Certification
actually i saw a used one in the sale ads, but he wants as much as a new one so i dindt see much use in looking at it, i dont know what they weight , but i have herd conflicting info on the swap for tubular units, some say as little as 25 lbs diffrence and i have herd almost 100 with a rack conversion, no proof on either and i am not ready to drop a grand to find out lol
#34
Re: SFI 25.5 Chassis Certification
me neither....bmr's website claims that a stock k member and motor mounts weights 54.5 lbs....i wish that would've weighed dad's old one and the pa racing unit he put in before we swapped them...then i'd know for sure...
I think that if you go with the pa racing k member without spring mounts, their arm arms without spring mounts, a manual aluminum rack and pinion steering and coilovers that you may save 50 or 75 lbs tops...not 100% sure though...
I do know that pa racing appears to have the best price by far....spohn, bmr, and aje are like twice the price for some reason..unless all the other 3 come with a arms and the pa racing unit doesn't....
I think that if you go with the pa racing k member without spring mounts, their arm arms without spring mounts, a manual aluminum rack and pinion steering and coilovers that you may save 50 or 75 lbs tops...not 100% sure though...
I do know that pa racing appears to have the best price by far....spohn, bmr, and aje are like twice the price for some reason..unless all the other 3 come with a arms and the pa racing unit doesn't....
#35
Re: SFI 25.5 Chassis Certification
i am leaning twords the pa k-member also i dont think the others come with arms either, i think its alot of paying for the name, i am not shure, some of the others cant accept a stock style arm and that makes me think they change the geometry on the lower arms, just guessing havent seen one in person to see if they moved the piviots. my steering box is shot and has lots of play in it so i might as well put a rack in, i dont think i am going to use the pinto rack though its too long and will change the bump steer alot through the range of motion. got 2 pic that show how much i use lol
#36
Re: SFI 25.5 Chassis Certification
My plan is to lighten the car by any means, tubular k member (probably pa racing), a arms, coil overs from and rear...back half with ladder bar or 4 link, add some structural support to cage, gut my doors out, gut the rear quarter skins out, smaller fuel cell, take the 130 lb weight outta my rear bumper, th400 with transbrake, 8" torque converter, 32 inch tires, maybe run the cage thru the firewall and gut the inner fenders and some of the core support out, aluminum floor in back, get rid of heavy torque arm, 4 coil springs, all new brakes(stockers aren't working so well), and just shave a little weight where I can...
My goal for next year is to run a 9.99 with no nitrous....I hit the button twice this summer, broke 1 bellhousing and broke all the forward gears the second time....i understand the 400 is going to hurt a little, but if I perfect what i have and take time to set it all up right and tune it, it may go 9.99...we'll see...the mph is there at 129, just not my 60's....and that's partially from parts failure not allowing me to tune too much...I had really bad luck this summer with transmissions, and msd boxes, so I was just happy to make some clean passes...but I'm still learning, like i said, the car came from the junkyard a year and a half ago, and i've raced it two seasons....one with a sbc and one with a bbc...and college 3 hrs from home limits the time i have to work on it during the year....but this is my final year, so next year will be better hopefully....
My goal for next year is to run a 9.99 with no nitrous....I hit the button twice this summer, broke 1 bellhousing and broke all the forward gears the second time....i understand the 400 is going to hurt a little, but if I perfect what i have and take time to set it all up right and tune it, it may go 9.99...we'll see...the mph is there at 129, just not my 60's....and that's partially from parts failure not allowing me to tune too much...I had really bad luck this summer with transmissions, and msd boxes, so I was just happy to make some clean passes...but I'm still learning, like i said, the car came from the junkyard a year and a half ago, and i've raced it two seasons....one with a sbc and one with a bbc...and college 3 hrs from home limits the time i have to work on it during the year....but this is my final year, so next year will be better hopefully....
#37
Re: SFI 25.5 Chassis Certification
yup lighter is better, thats alot of work to go 9.99 i think, no i know you can get there without the backhalf. I have no idea how the turbo 350 in mine is working, it has 900 hp going through it right now, (5.78 1/8 mile 1.28 60 ft on the rear wheels) and sometimes msd's just suck. there are some lightweight internal 400's out there they still hold plenty of power. i have some pics i will post to show you a few things , i will do that tomorrow..oh wait later today lol
#38
Re: SFI 25.5 Chassis Certification
Well, thanks for all the advice...I'm not saying that I need the backhalf to go that fast, I just need to tune what I have...I think that with a transmission that holds up and a reliable motor like the one I have, I should be able to get enough track time to fine tune stuff and get it into the 9's with no nitrous....that's my goal at least...my problem this summer was lack of quality track time...
It was fine until after Pinks All Out, then I changed from a 3.89 to 4.30 gear, changed from a TCI 10" converter to a BTE 9" converter, rejeted the carb, changed squirters and jet extensions...thought I had it good to spray, flipped the switch, hit the gas, and BAM, transmission hits the floor...and it was downhill from there....broke that bellhousing off, broke the reverse drum in another one, broke a second belhousing, and just broke all the forward gears out of another one 2 weeks ago, but haven't had time with school to pull it and see what happened....I'll get it all worked out here this winter though, and get some more good runs this summer to work the bugs out...I know my motor is reliable and my rearend is reliable, so that's not an issue, it's just that my transmission was my weak link this year...
Are you running a midplate on your car? You mentioned it above...if so do you have any pics of that? It's really tight in there getting to the bellhousing as is, that's my only objection to a midplate...I do have a plate on the front, but it's getting canned for solid motor mounts this winter....
It was fine until after Pinks All Out, then I changed from a 3.89 to 4.30 gear, changed from a TCI 10" converter to a BTE 9" converter, rejeted the carb, changed squirters and jet extensions...thought I had it good to spray, flipped the switch, hit the gas, and BAM, transmission hits the floor...and it was downhill from there....broke that bellhousing off, broke the reverse drum in another one, broke a second belhousing, and just broke all the forward gears out of another one 2 weeks ago, but haven't had time with school to pull it and see what happened....I'll get it all worked out here this winter though, and get some more good runs this summer to work the bugs out...I know my motor is reliable and my rearend is reliable, so that's not an issue, it's just that my transmission was my weak link this year...
Are you running a midplate on your car? You mentioned it above...if so do you have any pics of that? It's really tight in there getting to the bellhousing as is, that's my only objection to a midplate...I do have a plate on the front, but it's getting canned for solid motor mounts this winter....
#39
Re: SFI 25.5 Chassis Certification
yeah its hard to get a car to do what you want with limited track time, i had something like that happen too, i was running a local friday night thing and had some backfireing so i did a leakdown check to see if i hurt the bottom end, and i had some leak down in #3 so yanked the engine found i had a spun bearing..and it probably had been that way awhile, so rebuilt the engine and replaced the suspect coil, took it to the track and had no time on it made a few motor passes all good, put the bottle in, forgot to turn down the start percentage and wham past the rear bumper (i was told the rear wheels were off the ground) that mess up things a bit, still went 146 mph after lifting. but back to the topic, i have a mid plate and i have a few pics, i have the tci mid plate with the flywheel shield, you probably are using the bigger flywheel so it wont fit, but you can install a regular one in the same mannor, breaking bellhousings is usually a result of something being able to move too much like if you twist the chassis alot (and with a big block thats not hard) let me up load those pics
#40
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From: Boosted Land
Car: 92 Z28
Engine: Boosted LSX
Re: SFI 25.5 Chassis Certification
lotts of good info....
hey car_fixer If you need some photos hosted shoot em over to me in an e-mail.
fstfbdy@gmail.com I'll add em to the rest of my collection online.
hey car_fixer If you need some photos hosted shoot em over to me in an e-mail.
fstfbdy@gmail.com I'll add em to the rest of my collection online.
#41
Re: SFI 25.5 Chassis Certification
Car_fixer...thanks for all the good information here...this is exactly what I am looking for...it's hard to talk to some people about how the car leaves and what should or should not happen during the run...I've heard it all...ditch the th350, ditch the torque arm, turn the bottle on, build a bigger motor...not many people wanna help with what I have to work with...the car is going to undergo an extensive amount of work this winter to strengthen my weak points, and get it able to make some good clean runs...my biggest problem was breaking a transmission every 3 weeks, then my msd multistage retard box was messed up and the car wouldn't start...try and trace that one...I bypassed everything and switched everything before I figured that one out....then my fuel pump wouldn't keep up on the nitrous, then I broke another transmission, then school started again and I only have time during the weekends to work on the car....thank goodness it's the last year...
I do appreciate the help, and would like to see some pictures if you have some....
I do appreciate the help, and would like to see some pictures if you have some....
#42
Re: SFI 25.5 Chassis Certification
ok pics
this pics are from the pass wheelwell still on the trailer, so its not easy to see everything, it shows the idea though, i used angle iron on the end of the plate after i cut it to fit (jigsaw with a fine tooth blade worked best and use some spray lube on the blade while cutting) and i made triangular gussets from the scraps i made it so that the engine could piviot downwards to get to the trans bolts (i still have poly engine mounts in the stock location) the framerails there are pretty thick so i just seam welded the area and attached the angle iron to the rail tacked it with the engine on the mounts and the trans bolted up and in place on its mount so that things werent stressed i then welded nuts to the top (use flange nuts with the plating ground off easier to weld) so now its just 4 bolts more to get it out. i have some other pics but you cant see the plate from the top so there is no use in posting them, also dont use all solid mounts, in fact a gushy stock rubber mount on the trans is probably best but a mid plate should prevent further trans housing failures
this pics are from the pass wheelwell still on the trailer, so its not easy to see everything, it shows the idea though, i used angle iron on the end of the plate after i cut it to fit (jigsaw with a fine tooth blade worked best and use some spray lube on the blade while cutting) and i made triangular gussets from the scraps i made it so that the engine could piviot downwards to get to the trans bolts (i still have poly engine mounts in the stock location) the framerails there are pretty thick so i just seam welded the area and attached the angle iron to the rail tacked it with the engine on the mounts and the trans bolted up and in place on its mount so that things werent stressed i then welded nuts to the top (use flange nuts with the plating ground off easier to weld) so now its just 4 bolts more to get it out. i have some other pics but you cant see the plate from the top so there is no use in posting them, also dont use all solid mounts, in fact a gushy stock rubber mount on the trans is probably best but a mid plate should prevent further trans housing failures
#43
Re: SFI 25.5 Chassis Certification
Thanks for the pics...I'm running a small 1/4 thick steel plate bolted to the front of either head (3 bolts), bolted to a peice of angle welded to the frame rail area...I don't have any pics though...I have stock motor mounts and had a soft worn trans mount until about 2 months ago when I replaced it with an energy suspensions urethane mount...that seems to have helped the bellhousing issue, but the internals keep breaking...the car runs smooth the hole way down the track, I never felt vibration until I just broke the last transmission 2 weeks ago...but there is no sign of an external crack in the case, and fluid pooring out the overflow hole...I am pulling it this weekend, so I'll have a better idea, but this one is kind of weird. I have park, reverse, and neutral, but no forward gears...and low gear lunges about 3 ft in reverse then stops...I'll update when I find something out...
The plates on the front of my motor are getting tossed this winter, and I'm going to throw a set of solids in it...and keep the energy suspensions trans mount...you think that'll be any better? Someone told me to put a bar on the plate on the driver's side in case the trans and motor are moving frontwards to backwards, but that's too hard to determine for sure...I think that solid mounts and a soft trans mount will work...maybe...
The plates on the front of my motor are getting tossed this winter, and I'm going to throw a set of solids in it...and keep the energy suspensions trans mount...you think that'll be any better? Someone told me to put a bar on the plate on the driver's side in case the trans and motor are moving frontwards to backwards, but that's too hard to determine for sure...I think that solid mounts and a soft trans mount will work...maybe...
#44
Re: SFI 25.5 Chassis Certification
it would probably work but i will say not to do it, solid mounts will not allow the engine to tilt, and you wont be able to get the trans out unless you modify the tunnel. the hardest thing about the mid plate is cutting it, otherwise its all easy mig work. it will get alot of twist out of the car if the cage is good, but i think you said you were going to add x's in the doors if you dont have a diagonal in the roof i would say add one, especially with that big engine out there. adding just a front plate probably adds to the twist since you are applying the torque way out front. if you still have engine mount in the car they will be the limiters so you wont need a front/ rear limiter thats only if you have no mounts. i also have a csr trans shield on the trans that is alot worse to deal with then the mid plate, but it keeps me away from the turbo 350 that im putting 900 hp through , dont know how it works, i also dont know what that stock driveshaft has in it but i think it will see 8's
first i have to install the new fuel pump. also need to shorten the torque arm, the fronts get a little too happy so i can only start the nitrous at 20 percent (225 shot 20 percent is like uh 40 hp or so)
first i have to install the new fuel pump. also need to shorten the torque arm, the fronts get a little too happy so i can only start the nitrous at 20 percent (225 shot 20 percent is like uh 40 hp or so)
#45
Re: SFI 25.5 Chassis Certification
I'm close to removing the plates and putting the chain back on the driver's side like I had with the small block...didn't have any problems there....I can't tilt my motor now unless I take the front plates all the way off, which requires me to remove my alternator and everything, because I made a nice bracket so it mounts to the plate on the pass. side. I think that I need to just ditch the front plate and go back to the basics. The basic stuff worked fine, I just didn't want to chance any failures, and now I have a weak point, my transmission...and I can't afford more than one th400 for next season...my th350's were pretty stock with mild shift kits, and footbraking the car...the th400 is coming with all the goodies...so I don't want it to break at all...but I'll still probably foot brake most of the runs....dad's car 60ft's 1.25 on the foot brake leaving at 2000rpms....and has went 8.12 @ 174 with a 3.60 gear and a 29.5 tire out back...
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And my chassis is stiff..I can put the jack under a front a arm and can lift that wheel, and the opposite front and rear tires in the air easily...it's my suspension that's spungy I think...
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And my chassis is stiff..I can put the jack under a front a arm and can lift that wheel, and the opposite front and rear tires in the air easily...it's my suspension that's spungy I think...
Last edited by Little Z28; 10-30-2007 at 11:17 PM. Reason: Automerged Doublepost
#46
Re: SFI 25.5 Chassis Certification
not according to the pics up there it could be stiffer. oh yeah as far as suspension roll, got a crappy pic of the anti roll bar
look in front of the bracket the gas tank is on thats where i put the bar the ends are where the cage is attached to the body its also plated, i have a better pic of the end i havent put it up yet and im tired lol
look in front of the bracket the gas tank is on thats where i put the bar the ends are where the cage is attached to the body its also plated, i have a better pic of the end i havent put it up yet and im tired lol
#50
Re: SFI 25.5 Chassis Certification
What do you mean???
Are the bars that link the to the rearend mounted perfectly verticle?? Does it hurt to angle them slightly? I've seen pics of the sway bars, but we don't have any on our cars...