dizwiz24

Theres a lot of c4 bash talk.

In fact, even ECS believes the C4's take too much work to make fast.

Well, Id like to debunk that myth:

https://www.corvetteforum.com/forums...tor-setup.html

Heres an example of what makes the c4 BETTER to mod than a later model corvette.....

If you wanna boost your stock bottom end, just do it! Like I did mine.
(Thanks greg@blowerworks)

illenema

Never impressed by a C-5 look. They can have them. Rather do a ls swap in a c-4

LT1inaMGB

How about some more details on your setup - how much boost, cam, compression, etc. I'm interested because I have a boosted LT1 with a stock bottom end.

Jim

Jim

dizwiz24

510 rwhp at 5500 rpm (there was more in it but i ran out of time on the dyno)
Afr195 comp ported heads..61cc chambers to make it 9.7:1 static compression
1 7/8 (bigger than i need) arh headers/3" exh
224/236 cam 114 lsa
blowerworks meth inj system
P600b max boost of 12.5 psi at 6k. Blowerworks 8rib dedicated drive belt
Msd6
ostrich
2 fuel pumps -walbro 255 l/hr feeding a gsl392???
60 lb/hr inj
6spd


I do not spin higher than 6000 rpm bc im happy with the power im making and no need to take risks

LT1inaMGB

Thanks. I have a point higher compression than you do but I'm only running 7-8 psi and I haven't encountered any detonation yet. I also have water/meth injection and the quench is just below .040". I am more confident now after reading your experience with the stock bottom end.

dizwiz24

Ok well this will make you feel better also:

Does your screen name indicate what you have? (Ie. an LT1 in an MGB)

If so: then you are in good shape.

a GM powertrain engineer told me the vehicle weight is a factor in their calculations of the reciprocating asembly durability. Specifically the crank.

Corvettes, and especially MG's\, are comparatively 'light' compared with the other V8 bearing machines (trucks, buick roadmaster, SUV)

The stock crank should live pretty well in a lightweight, boosted car, at our power levels

I do get occasional detonation retard, up high, where as little as 1 degree of timing can make all the difference.

I would rather have 1 degree less timing up top and not upset the knock sensors, then having mild knock cause the knock sensors to take out 6 degrees right then and there.

Again, I caution dont take it over 6000.

LT1inaMGB

Yes it does. The car is an MGB roadster widened 11" with C4 suspension front and rear. I don't take it much past 5500 rpm since the revs come so quick. When I had it tuned I had the guy take 2 degrees out just to be safe with the fuel quality being what it is, I think it has 23* total under boost. I don't really need the last hp out of the engine - 465 rwhp and 479 rwtq in a 2600 lb car is plenty to get your attention and about all I can get to the ground.