IrocZS383

does anyone have the specs for the something old something new tpi longblock in gmhtp. in the current issue it says they dyno tested it as a 355 vortec headed and sdpc vortec base accel large tube runner tpi, the produced 416 hp and 490 tq. Does anyone have any specs on this motor such as compression ratio, they list the cam specs in the current article but this is part 4 and you cannot look up the other 3 parts online. thanks for your help in advance.

89Nighthawk

Boy those numbers look familiar, see my sig.

IrocZS383

only diff is that they are only running a 355, not a stroker combo

3.8TransAM

It doesnt matter.

No one here will take the time or spend the money to do it right like they did.

People have no concept of what blueprinting an engine really means.

U index the lifter bores, align hone cam and crank, etc.

Thats why when you buy something from Lingenfelter it costs so friggin much, all this has been done, whereas 95% of street builds(prolly more) dont go to these lengths.

Engines setup like that will last longer and make more power than a "rebuild" what most people do.

Either way, it seems impressive thus far, of course I dont care what it does on a stand, I want to see RWHP in a car. Also use a real accesory drive and not an electric water pump.

And throw away the DFI that a stock ecm can do better than.

later
Jeremy

3rdgenZ

iTrader: (1)

i cant find the mag, i know i have it.

but i can tell you what i remember. the comp ratio was around 10.8/1(maybe even higher, but dont remember off the top of my head)
they ported the vortec's out 182cc on the intake runners.
they used 1.6 RR, crane i belive. they used a stock crank with mantly conn. rods and forged flat tops (dont remeber what kind). they put a five angle valve jobs. they had extrude honed Accel base and runners with the 58mm tb.24# accel fuel injectors.

the one thing i must say is that they made good hp with a mild cam. that tells me that those head flow great. if you what anymore info ask it and ill try to remeber. or i could go find the mag .

1989GTATransAm

iTrader: (3)

If memory serves me right the cam was 210 degree on the intake and 220 on the exhaust. Lift was around .510". Those numbers were on a dyno stand. So nothing but the basic accessories. The key to horsepower is the heads.

BadSS

4.030 bore - Probe -4cc Flat tops, small tapered skirts, 461g with pin, 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 it'll be in the next installment. That's extremely good intake flow numbers from a Vortec head - it would be interesting to know the cost associated with getting those numbers.

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. Maybe that'll be in the next installment also.

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

1.75" dyno headers (long straight pipes coming off the heads) into dual 2.5" Flowmasters (series not indicated).

Gunner823

iTrader: (2)

Could you even hope to run premium pump on that compression with iron heads?

GOY

As long as the piston top is designed to work with a quench style head, yes Premium fuel could be run. It would be "Close" however.

1989GTATransAm

iTrader: (3)

There is a car here locally that is running the iron Vortec heads and 10.5:1 compression and with 91 octane. However it took quite abit of tuning to do it.

IrocZS383

yes i agree with them, it would be close but it all depends on your quench, and what your dynamic compression ratio is, i have checked it for this engine, which is why i was curious about the specs and it is running a dcr at right about the limit for pump gas but it is there