IROCZ1989

iTrader: (1)

I have finalized a engine combo with my builder.Here is the specs:

Scat 4340 stroker crank
Scat 4340 h beam rods
Srp flat tops
Afr 195 starting with a 74cc chamber,then angle milling them to 64 to run 11.1 compression
Have not yet picked the cam
Intake will be a superram and the new accel dfi.

Some of my concerns are with the compression and the angle milling of the heads.
I trust my builder and he's been in buisness over 30 years,he has has reapeatly told me that 11.1 compression on the street will be fine.He told me with the efi and a good cam the motor will run on pump gas.

My other concern is the angle milling of the heads.My builder told me the bigger 74cc chamber over the 68cc are deeper and a better starting point than the 68cc head.He told me the head needs to be milled down to 64 to get the 11.1 compression,and there is a Hp advantage to standing the valve up straighter when the head is angle milled.I called Afr and they comfirmed this with me that they also always start out with the 74cc head when the angle mill a head and comfirmed the 74cc is a more opened up chamber.

We are shooting for 500hp on motor.Any thought please.Thanks

Jstcrzyengh

iTrader: (2)

11:1 seems a bit high for pump gas even on AL heads. Though all we have here is 91 octane. I will be running 10:1, and now I will have to be on 91 at all times.

DreamState21x

My friends mustang has 11.5 and when he put 91oct in it, it had all sorts of engine pings and knocks and ran like crap...

Jstcrzyengh

iTrader: (2)

That's what I was thinking. I am going to run a 10:1 compression ratio, because of the head gasket I am going to use. Essentially giving me a 9.35 with iron heads. Wanted to stay at 9 or under because going boosted, but oh well.

owned

I think you'd be better off going with a stealth ram vs a supperram. To get 500 HP on a small block, you are going to need some real high rpm airflow, while the superram is still a relatively long runner design.

11:1 compression can be done on pump gas, although it is right at the limit. If you are anywhere above sea level, it won't be an issue.

Jstcrzyengh

iTrader: (2)

I would agree with either the stealth or mini ram. I have to go with super ram for emissions purposes.

kevin89formula

i have 10.25 to 1 with no problems.

190 afr heads, 68cc.

i would pick the cam out before i milled the heads and get the opion of the cam person as to how much more power 11 to 1 is going to give you.

will the milling angle cause intake gasket sealing problems?

depending on the cam you chose will the angle milling cause any problems with the pistons needing to be machined for clearance?

Jstcrzyengh

iTrader: (2)

What do you guys run in Texas as far as octane goes? Were stuck with 91. Don't you guys get 94 out there?

IROCZ1989

iTrader: (1)

I am trying to cut down the costs of the motor some and to angle cut the heads would be 275.All together the longblock will run $6600 with 4 bolt mains studded and studded heads.All I will need is the intake amnifold to finish it up.I was leaning towards the Accel unit because for $3000 you can get the whole superram setup,with the accell tb,fuel rails,injectors and all new sensors,+ the new DFI computer and harness for $3000.I have not seen any fast cars out there yet running the stealth ram and My builder doesnt like the Holly efi stuff as he has used all 3 the accel Fast and commander.Any other suggestions?Thanks

87transam5.7tpi

11:1 sounds pretty high. i'd try to get down to 10:1 or so. I'm going to be running about 9.25:1 because I'd going to be boosted too. do you have any other plans for the motor later on? you may want to take that into consideration.

Josh

DreamState21x

yeah we only have 91 here.. it sucks cause im from fl. and we have higher there..

87WS6

iTrader: (1)

Actually there is a 7-11 on Greenville and Park LN that has 93? I know it's over 91. It was the first time I ever saw it.

DreamState21x

there is a love station on the way to dallas that has 94, but that's like 21/2 hours from here..

85TPI400

Just thought that I would throw in my opinion. 11.1 does not sound unheard of. I have ran 10.25:1 on a trickflow headed 350 with a mild cam 210 in. 216 ex duration w/114 lobe sep. this obviously didnt bleed off much of the compression and had no problems with pump gas. My guess is if you are aiming for 500 HP on the motor alone, It is going to have a big enough cam with a bit of overlap. I would listen to your engine builder, he has been in buisiness for 30 years and it sounds like he knows what he is talking about, (not the type of person with only the knowledge to build stock or mild smallblocks).
Good Luck!

Kingtal0n

just want to add that with a long runer design like that 500 on motor will be very hard to attain. if you will need to spin it past 6500 RPMS to even be close the making that kind of power, probably closer to 6800 rpms, and thats with a very high peak torque and a big duration cam, and even then the long runners will be holding you back.

If you peak torque at 6500 RPMS (roughly 400 Ft Lbs for a N/A 350 motor) you will see 495 Horsepower. but thats a lot of cam to peak torque at 6500. do you plan on street driving this thing?

I think 450 is reasonable, but 500 is pushing the limits of any long runner intake.

HiTech5

iTrader: (4)

My 383 has the angle milled AFR's. The combustion chambers are 62cc with flat top TRW's and a zero deck. The compression calculates to 11.6-1. I can run the motor on 93 octane if I pull the total timing down to 36 degs. When I use 100 octane, I can bump the timing up to 38 degrees and make more power. I have DFI so adjusting timing is rather easy.

Camshaft has alot to do with fuel compatabitlity. If you run a small cam with very little overlap, the motor will be very fuel sensitive. With the AFR heads and the good intake to exhaust ratio that they have, I recommend that you use a single pattern cam. Comp can custom grind a cam for you. If you want to use a hydraulic roller, go with a Comp XE lobe, 236/236 .555/.555 lift and have ground on a 112 lsa 2 degs advance. This cam will give you power to 6300 with a very strong midrange and top end.

As far as intakes, my preference is the MiniRam. I have had long tubes, SLP runners, SuperRam and MiniRam. My choice is the MiniRam.

www.geocities.com/dzperf

L98IROCZ89

My father runs 11:1 compression on 93 octane, sunoco ultra 94 when possible. This motor is a dual-quad carburated 427 FBB with edelbrock aluminum heads. Engine runs just fine on this octane. Just throwing that out there for you, FYI kinda thing.

89gta383

iTrader: (5)

I'm having sealing problems with my angle milled heads. Mine started at 79 cc and are now 63cc. I have to use a thicker intake gasket to get it to seal.

If I were doing it all over again, I'd let the pistons make the compression with the head gasket and deck height instead of taking off so much from the heads.

icecold

i just went with the regular milling and went to 64cc and afr charged me 100 as i remember.but i also decked the block and am running 10.0-1 and 6 psi boost on 93 octane with little or no knock.so my .02 is you should be ok if you can tune it properly.otherwise why not drop it back to 10.5 -1 you will loose very little and have a larger safty factor.
pete

REDZ28

Listen to your engine Builder!

camarojoe

The combustion chambers on the AFR 195's are awesome for letting you run higher compression on pump gas. They're so much cleaner than just about every other aftermarket head. You won't have to worry about detonation with 11:1 comp. unless you advance the hell out of your timing. But you can control all that with your dfi setup. I'm running between 8-10 degs. base timing with about 10&1/2 comp. and have know signs of detonation whatsoever.

I agree with HiTech about the cam. That's similar to what I might switch to when I pull the engine again (I've got major blowby). Also, to get 500hp you're going to have to port your super ram runners thoroughly as well as the base.

IROCZ1989

iTrader: (1)

I went to another shop for a second opinion.He had a llittle different take on the buildup.The first builder I should have mentioned does not do many efi builds,the second specializes in them.The second builder I was much more comfortable talking with and his take on the angle milling was it wasnt worth the 275 for that little bit of power,money better spent elsewhere.He had at the shop a 402 LT1 with a Vortech after cooled,fast system 900 hp on 100 octane.And his personal car is a 396 with the bottle almost 700hp so experience is a factor and he was telling me it was better to have everything done at one place(build,and tune) to minimize problems, if any came up.These are local shps in Ma.I think Im going to go with the second builder.I feel very comfortable with his imput and he really listens to the questions and concerns I had.If anyone is interested in knowing the shops names I will gladly post them.


On another note I am now stumped on the intake,The car will be street driven,yes but not daily.Anyone have any cam,intake combos that net about what Im looking for on motor?Nitrous is not an option now but Might be a consideration in the future.Thanks

One more thing,is it worth the extra money to get the competion ported heads from AFR?Thanks

badgta

iTrader: (4)

making it up with the piston is a very good idea....... yeah milling is a way but it removes metal from the head in which you might need to mill one day if the head becomes slightly warped..... decking the block lets the piston come up further, like milling it lets the valve get closer, and then you have to consider piston/ vavle clearence, but i'd really say on a very high lift cam....

heat is what causes detonation.. hot spots that ignite the fuel...... best things you can do easy and cheap to help fight this is cold intake ait temps and a 160* thermostat with say 2 1/8 holes drilled in it...... it would tho keep you in open loop on a thirdgen tpi setup... aluminum heads tranfer heat faster, thus cools hotspots faster which lets you run higher compression.... but you have to maintain a certain compression to keep any thermal efficency.........