S105.7

anyone see this buildup in GM High Tech? it was a 355, Vortec heads, Accel intake/runners. the cam was a crane 210/220* and had .500/.510 lift.

i was wondering if anyone knew a little more about this engine, and how they got so much power out of a LTR setup. i know that this much is fairly uncommon.

my 305 is crapping out on me, and i need to build a motor, so any info will help. thanks, Jim.

heres a few pics of my ride. its not a 3rd gen, but where else can you get this much TPI info.

3rdgenZ

iTrader: (1)

piston volume= .4cc
combustion chamber volume= .61cc
"ported vortec head"intake runner volume= 182cc
compression ratio= 10.95
24#accel injectors
extrude honed accel base and runners.
the TPIS base and good set of runners like AS&M or TPIS (for an ltr setup) will be just as good if not better.
the cam was installed at 110.5 degrees to advance it 3.5 degress.
1.5 comp RRs

there will be an update coming soon.
edit: sorry but the TPIS base wont work with a vortec heads, i should have said that earlier.



i see headers on your blazer. what kind are they? and what kind of power do you want from your motor?
would you be willing to swap to a 350?

S105.7

ah, i didn't realize they used that much compression. i also didn't know that they extruded the intake, that makes sense. i got a CHP issue where they tested SDPCs vortec manifold with a HOT cam, and it only made 350hp.

its good to know that TPIS' stuff is just as good. i prefer those runners over the accels; hard to tell from stockers.

thanks for the support. i posted about a year ago, and didn't get a very warm welcome. come on guys...its still a chevy!

BadSS

4.030 bore - Probe -4cc Flat tops, very small tapered skirts, 461g with pin (very light), small low tension rings, 3.48 crank, Manley I-beam 6" rods. 10.95:1 compression ratio.

Align bored mains, block decked to 9" off the aligned mains, register plate used to locate the cylinder bores, aligned and bushed lifter bores. Stock oil pan with windage tray.

Vortec heads flowing 265/185 cfm at .5 lift on the "rough cut" port and before the 5-angle valve job. Intake volume was 182cc, chamber volume was reported 62cc in one place, 61 cc in another. Flow sheet was promised, so maybe they'll come through on it. Best guess they ended up around 270cfm - which out flows the majority of out of the box aftermarket heads.

Cam is a Comp hydraulic roller 210/220 - 114 spread installed at 110.5 Intake Center using Cloyes Hex-Adjust chain. Lift is .500 / .510 with the aluminum Comp 1.5:1 full roller rockers.

Scoggins Dickey Vortec base and cast Accel long tube runners. Plenum, runners, and base rough ported THEN sent to Extrude Hone. Article said they would provide flow data before and after with the intake bolted to the heads - that doesn't look like it'll happen.

58mm T/B, 24# injectors, dialed in with an Accel DFI.

1.75" dyno headers (long straight "dyno" pipes coming off the heads) into dual 2.5" Flowmasters (series not indicated). A "real" set of headers would drop peak a good 10 - 15 horses,, single and twisting 3" exhaust even more.

3rdgenZ

iTrader: (1)

the TPIS base wont fit vortec heads sorry(i forgot to say that). and in that CHP issue they only used stock runners and the base was unported, i belive.
i educated myself they used accel unported runners.

S105.7

good eye! those are 1-5/8" sanderson swap headers. they are shorties if you aren't familiar with S10s. as for the 305, i have a boat that needs a new mooring! i take it from all this info, they build the bottom-end in a previous article.

my goal is around 325-350rwhp from a LTR, and 100hp hit of juice is not out of the question. how does this sound?

scat crank and rods
flat top pistons
zero decked
Vortecs
-mild bowl job
-port clean-up
-beehives
-1.94/1.50s for now. 2.0s max right?
similar cam (hows the XFI line?)
Edelbrock base and TPIS runners (SDPC any better?)
75-100hp shot of juice

i don't have 5 grand to spend on a motor right now, but with this setup i can always impove as the money rolls in. thanks for all the info guys. keep it coming, Jim.

S105.7

yeah the whole top-end was as cast. HOT cam+TPI= crap! im not sure of the bottom end either. can those accel runners be siamesed? how about siamesing the stock base? i have heard that it causes too much turbulance.

3rdgenZ

iTrader: (1)

325-350 is a little tall, but is doable. this should make things a little easier.>
http://www.sdpc2000.com/catalog/2172...ke-Headers.htm
i would diffenetly recomend soom porting to the heads. what you said before should work. the cam they used in the article would be a very safe bet. they also have TPIS ZZ9 cam, gmpp zz3 and 4, and of course the hot cam.
http://www.thunderracing.com/catalog...&vid=6&pcid=51
as far as siamesing the base, i dont know but you can do a search on the site. i think i have seen it before.

MARO-MAN

Cool Blazer! You don't see many 2WD Blazers around here, much less with TPI and that clean.
I like you air cleaner setup. Were did you get the pieces for it, then you just added to the wiring for the MAF? Wonder if that setup would add any power to my Iroc.....hmm...
-Nick.

S105.7

thanks for the complements. i worked hard making it look like that TPI belonged in there! the rubber pieces were from stealth conversions. they ran me about $75, but it came with 3" aluminium tubing where its clamped. actually the wiring is unchanged. i pulled about 2" or so from the loom, and it worked out just fine. might not be the best flowing with those sharp bends, but it gets the job done. it makes plenty of noise too.

Orr89RocZ

iTrader: (20)

highly doubt that 416hp vortec TPI setup. that cam is not big enough, atleast it seems to me that it aint. i have seen a few combos on this board with alot bigger cams and better heads with fully siamesed intake runners make 310-330whp. thats very powerful numbers out of a 350 inch motor.

they had a 460hp stock extrude honed TPI setup on a 383 with ported trickflow 195's and huge 236/242 cam. no way a 350-355 with that cam will make 400+hp. just dont see it. that cam looks like the compucam 210/220 that works well with mild TPI setups with stock computer..but by no means is a powerful camshaft


with cleaned up vortec heads on big compression, and bigger cam with fully ported runners and base, you might beable to get 320-330whp out of it.
i'd definately shoot for 11:1 compression and get a cam that will keep dynamic compression ratio happy but a good bit of duration..probly in the 220ish range with lift near .500-.510". althought ZZ9 is a nice cam. i definately like the sound of the 224/230 cams or custom grind like 226/234. should be a killer TPI setup makin upwards of 330whp or possibly more based on a good tune

accel runners cant be siamesed..but edelbrocks and SLP's can. accel runners are just individual tubes similar to AS&M and TPIS

S105.7

well, i need a new crank, so a 383 is definatly an option. just seems that a 383 and LTR is going to make too much torque for a daily driver, which is just what my Blazer is.

Guest

Dont worry about siamesing the base since you're already going with an Edelcrock. I would port it though (or have it done), as cast its not all that great. And go to the manufacturer on the runners, Arizona Speed+Marine, not TPiS unless you want to pay more for the same thing. Might want to do a little searching on the ASM site too, if you do you might find a slightly better price.

The XFI cams are pretty nice, but may not match well with those heads because of the lift. You'll want around .500 lift with the Vortec heads from everything I've read and the XFI cams fall into the .570 range with 1.6 rockers.

3rdgenZ

iTrader: (1)

actually a 383 with a mild cam and good ported LTR setup would be a great daily driver. the only problem with have that much torque is that it will destroy your drivtrain. plus the vortec heads in the kit are too small unless you get the bigger 200cc vortec's, but thats more money.

TransAM Joe

iTrader: (6)

Something to think about: You can't just throw parts together like a big cam, high flow heads etc. and expect 400hp, you have to match the parts and assemble them with really tight tolerances. For example using a stock production 350 tpi rated @ lets say 245hp. Now lets start a build with a bare 350 block with 3.998 bores (yes I realize this is slightly too small). Take all the stock parts and assemble them with race tolerances, like measure each bore for the specefic piston size, file fit the rings, degree the cam in, mill the block, run shim head gaskets, measure and custom make pushrods. Basically blueprint everything. This alone will increase the efficiency and horsepower 20% and there is alot more to do. Combine this with hi po hand picked custom made parts and 416hp is not that hard to achieve. We build marine race engines and transmission everyday and 416 hp out of a 355 fuel injected naturally aspired motor is not hard.

S105.7

breaking drivetrains is exactly what im worried about. we all know how good the 10bolt is.

anyhow, thanks for all the replys. its all food for thought. im just trying to get an idea of what combos work, and what doesn't. might just see about fixing up the 305 and invest in some AFR 195s, and a new scat 3.75" crank.

3.8TransAM

Thats what I said in the other post about "something Old and something New"

99% of people here will never go to those lengths to assemble and tune any setup, so it wont happen for them.

SOSN is alot more than a bargain rebuild and cam swap.

later
Jeremy

Orr89RocZ

iTrader: (20)

416hp is not hard to achieve with a HSR/Miniram/even a superam, but i think TPI is pushin the limits with 350 inches.

whats the most n/a TPI hp you've seen? on a 350? its up there around 330whp i believe which is near 410-420 crank i believe.

3rdgenZ

iTrader: (1)

very nicely put.
did you see the flow numbers for those heads . you could spen 2k + on a set of heads like that. but thats one of the reasons iam going with a 383 tpi. HP isnt what iam worried abut as much as times. iam looking for high 11s or low 12s.

Orr89RocZ

iTrader: (20)

thats the thing about TPI cars..they make so much low end power that they get off the line very hard and thus make good ET's for the power.

a 383 TPI car is capable of making decent hp numbers...but the torque is where its at. it will come off the line and run very nice 330ft-1/8th mile times, and still have enough to carry thru on the top end to do low 12's even tho the trap speed maybe only 110mph.

magnum TPI in GMHTP i believe is a 396 TPI that runs high 11's at 113mph. take off that TPI and place a miniram on it..it will be low 11's at near 116-117 with same cam cuz it will gain so much topend yet still have enough low end.

3.8TransAM

The SOSN article basically made light of the fact that there is a lot of power to be had by examining and exploiting the basics

3rdgenZ

iTrader: (1)

once again . it makes me want to go and have my block put though some of the tests and procedures they did. ive also been looking at thermal barrier coatings. every little bit helps. i really want to be in the 11s with my tpi. i mean how sick would that be to be a the track with your stock looking LTR setup and run 11s with no spray. its a lot to ask but by looking at the numbers in the super rod artical "10 times the torque", i think its posible.

i also must say if your building your own motor. i advise you to pick up the lastest issue of "Engine Masters". there's a lot of good tips on building a pump gas motor.

S105.7

i guess i can walk away from this knowing one thing. 400+hp isn't just going to happen. they went through great lenghts to get those numbers. here i was just thinking they got lucky.

well i guess the best place to start at, is a solid bottom end. my 305 finally ate the big one today, so time to get that Scat crank!