Ksths2

iTrader: (1)

Ok, this might be lengthy stay with me.

I've ran a LS1 has 50k miles at the dragstrip for 4 years now on 150-175 shot with all kinds of mods. Well I hurt it last weekend at the dragstrip (not sure how bad yet) and I'm looking into new options.

Option #1 - I was convinced on a 408 build out of a LS2 or LS3 aluminum block by buying a short block from TSP or AES or SDPC but currently don't have the $$. & I'd like to not have to convert everything over (sensors, LS2 lifters etc)

Option #2 - I've got a spare LQ4 iron block that I thought about installing a TSP 408 rotating assy inside it but leary on any local machine shop doing the work here in Iowa.... but I can send it off to AES in Illinois or TSP etc.

Option #3 - I'm super interested in this option.....Has anyone redone a LS1 and made it super nasty? I mean, using my existing alum block (depending on how bad its messed up inside) and putting a 383 TSP 4" stroker crank in it instead???? without resleeving it or doing any machine work??? Cuz I really want to stay with the aluminum block since the LQ4 is 110lbs heavier...

Before you answer read what i'm wanting to do.

This will be installed into 2002 C5 that I 90% dragrace 10% street drive, this car is built tough and ready for more power. RPM Trans, diff, gears, braces, etc. BTW I want this thing to fly!! Low 9's would be cool --- 9.50's is the slowest I'd to see out of it.

While its all apart I'll be converting it over to E85 w/ a A1000 pump, & planning on putting either a Procharger Race kit (F1C 8rib) or the A&A kit using a YSI 8rib supercharger on it rather than continue with the N2O.

I'm planning on TEA L92 heads w/ LS3 intake valves, solid roller, Holley hi-ram, LS2 throttle body to go on whatever engine you guys help me decide to build.

You think the above combo would work on the existing LS1 block or go with other??

Ok..... lets hear it.

J Glen

Well at the end of the day it is up to you and what you want. If it was me I would use the iron block, and try to make up for the weight with the extra power you can make. Or you can look at other parts of the car to take off some weight. I would suggest a beefy valvetrain for that kind of power though. And just to add a little extra I would look into a custom cam grinder for your solid roller.

Ksths2

iTrader: (1)

I agree on the power vs iron block durability vs aluminum weight, I'm not super concerned about that but it'd just be nice not having to find that extra weight.

Above I did mention a solid roller but nothing saying I have to do that, the main reason I did that was trying to save weight on the valvetrain and figuring I'll have to turn this LS1 idea alot more rpms to get the same power out of it as I would with the 408??

mark21742

I went 408 iron block and have NO regrets at all and would do it again....if you don't have faith in a machine shop then go with your gut and don't take the chance. Find another shop.

bww3588

iTrader: (49)

The ls3 top end will not work on an ls1. Depending on how bad you hurt the ls1, more than likely, it is junk because of the thin cylinder liners.

Ksths2

iTrader: (1)

yeah I agree on the 408, the main issue with the machine shops around here are there aren't many and the ones that are decent haven't ever done LS engines....

bww3588, i just learned that last night, the reason is cuz the LS3 valves will hit the cylinder walls on that small bore LS1 right???

Looks like i'm back on the 408 idea

bww3588

iTrader: (49)

Yes. The valves probably won't even open. I would stick with the 370/408 idea.

mark21742

Another thing to look at is to properly bore/hone an aluminum block you need to use a torque plate...it is recomended to use one with an iron block, but an not absolutely needed since the aluminum blocks move around more while the heads are being torqued down.