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Ryan Stout
10-09-2009, 05:47 AM
Should I go 383 now while I'm doing it or just do a forged 355 build? I want about 9:1 compression and able to hold 650rwhp without me cringing every time I go WOT afraid I'm gonna break it. 4 bolt mains is a must, already talked to Lloyd about getting me a cam. It'll cost me next to nothing to make it a 383 right now, but its the supporting mods that are gonna kill me. I'm already set up for a 355, not the massive amounts of torque a 383 will make though. Thanks!

njrextreme
10-09-2009, 09:08 AM
If its not a daily driver, id say build it up to the 383. Take some time buying all the parts and then start on it. If you need it on the road soon, go w/ the 355. You know you will be kicking yourself when your not happy w/ the 355.

BLOWNDFIZ
10-09-2009, 09:10 AM
Go 383. Since you are goinf gorged everything the cost difference in the cranks is negligible.

Jay_rich
10-10-2009, 06:40 AM
Mine is a 383, its great but you need a crazy dish piston to keep the compression down with a stock head!
Get some nice JE pistons, eagle crank and rods should would as I am using all this stuff haha

Jay

Ryan Stout
10-12-2009, 05:29 AM
What do you recommend for pistons? I was thinking of SRP's 31cc dished pistons and a somewhat thick head gasket, but IMO it would be better to run a deeper piston with a thinner (than what a 31cc would use) gasket.

Jay_rich
10-12-2009, 09:47 AM
What do you recommend for pistons? I was thinking of SRP's 31cc dished pistons and a somewhat thick head gasket, but IMO it would be better to run a deeper piston with a thinner (than what a 31cc would use) gasket.

Mine is JE-28CC, .043 SCE copper gaskets and AFR 195 65CC comb chamber. I am at 8.65:1
Block has been Zero decked too.

Jay

CALL911
10-12-2009, 09:51 AM
I have custom Diamond pistons personally and would highly reccomend them.

As far as your original question goes; most guys just go with the 383. The 383 will not really yeild you any more HP than the 355, but it will give you more torque. Don't worry about the strength of one to another as you can make either easily hold WAY more than your goal of 650 RWHP. But if you were already planning on a 355, theres again really not going to be a ton of difference other than you will loose a bit of potential torque.

Ryan Stout
10-13-2009, 05:30 AM
So let me ask this, what would I really be gaining from a 383 rather than a 355?
I don't need any more torque thats for sure, I'd just like to make the same power from a low boost 383 as a higher boost 355. I have an alky setup I can always toss on the car if need be with the 355 though, and I can do a stock heads 355 setup and save a little cash to get a S60...

CALL911
10-13-2009, 07:22 AM
How much torque would depend on the setup of the 383 (heads, cam, intake ect.). The less restrictive the parts, the more torque you would see. As far as actual HP, the 355 can make just as much as the 383. Like I said before, your not really going to see an increase in HP from the 383 from the 355, more or less just a torque difference.

Ryan Stout
10-13-2009, 03:47 PM
I made 511tq at the wheels on my last 70mm setup before I went with a MP76 and a better tune. The more I look into it, I might just go 355. Would a 383 be any more unreliable? I've heard that if you spin a 383 to 6000rpm, its about like spinning a 355 to about 7500 due to the longer stroke and how much farther the rods and pistons have to travel in the same amount of time. I'd like to be able to cruise up to Indy (about 60 miles) without worrying if I'll break while playing around up there. Just weighing all my options before I really go through with it.

Thanks for the help Call911

CALL911
10-13-2009, 06:33 PM
I made 511tq at the wheels on my last 70mm setup before I went with a MP76 and a better tune. The more I look into it, I might just go 355. Would a 383 be any more unreliable? I've heard that if you spin a 383 to 6000rpm, its about like spinning a 355 to about 7500 due to the longer stroke and how much farther the rods and pistons have to travel in the same amount of time. I'd like to be able to cruise up to Indy (about 60 miles) without worrying if I'll break while playing around up there. Just weighing all my options before I really go through with it.

Thanks for the help Call911

Just like the amount of difference in torque, the reliability on the 383 would only vary upon what parts you build it with. 4 bolt mains, and higher quality parts will make it just as strong as any well built 355. Building a strong 383 is nothing new, tons of people have been doing it for a long time and throwing TONS more power than your goals are set to.

My 383 is extremly well built, and it sees 7,000 RPM boosted and I am more than confident that it will last well beyond 100,000 miles before I need to do any major maintenance on it.

Here's 7,000 RPM on my 383
http://videos.streetfire.net/video/Making-some-boost_145597.htm

Ryan Stout
10-14-2009, 07:21 AM
Holy shit, after watching your vids, I might as well go 383 while I'm in there. What heads did you go with? I was looking at a LE2 setup. Also, what crank and rods did you use? I emailed ohio crank and for a forged bottom end, they wanted $1700 for a crank/rod/SRP piston setup. Seems a bit pricey to me but I have a lot of research ahead of me. I haven't heard a lot about them really.

Fire67
10-14-2009, 11:48 AM
IMO, after building a wild blown 383 and driving a few blown 355 cars... For a street car, Id rather have a higher reving 355 with a stick shift tranny than a low end torque monster 383. The torque difference can be huge and my 383 makes way to much for the street.

CALL911
10-14-2009, 01:08 PM
Holy shit, after watching your vids, I might as well go 383 while I'm in there. What heads did you go with? I was looking at a LE2 setup. Also, what crank and rods did you use? I emailed ohio crank and for a forged bottom end, they wanted $1700 for a crank/rod/SRP piston setup. Seems a bit pricey to me but I have a lot of research ahead of me. I haven't heard a lot about them really.

I have AFR heads, Lunati sledgehammer crank, and Oliver billet rods. This is part of why I am confident my motor will last 100,000 miles under a moderate (15#'s) of boost. All together I've got more than $10,000 just in the motor, but I went with the best parts money could buy. You don't have to do it that way, but you'll get the most performance and endurance out of it if you do.


IMO, after building a wild blown 383 and driving a few blown 355 cars... For a street car, Id rather have a higher reving 355 with a stick shift tranny than a low end torque monster 383. The torque difference can be huge and my 383 makes way to much for the street.

Depends on your opinion :devil:

Ryan Stout
10-14-2009, 04:34 PM
IMO, after building a wild blown 383 and driving a few blown 355 cars... For a street car, Id rather have a higher reving 355 with a stick shift tranny than a low end torque monster 383. The torque difference can be huge and my 383 makes way to much for the street.

Thats kinda what I'm afraid of, I'd also like to buy a S60 this winter. If I go 355 I won't buy heads but just port match mine, and I won't need to replace my injectors I just bought. I guess I just need to think about it (or someone to talk me into it the night before I order parts haha).

Ryan Stout
10-14-2009, 04:35 PM
I have AFR heads, Lunati sledgehammer crank, and Oliver billet rods. This is part of why I am confident my motor will last 100,000 miles under a moderate (15#'s) of boost. All together I've got more than $10,000 just in the motor, but I went with the best parts money could buy. You don't have to do it that way, but you'll get the most performance and endurance out of it if you do.



Depends on your opinion :devil:


What are some other good brands? I hear compstar is good stuff too.

CALL911
10-14-2009, 07:53 PM
What are some other good brands? I hear compstar is good stuff too.

As far as what parts? Compstar makes decent parts. Best parts you can get for crank, rods, and heads are pretty much what I have in my motor and previously posted. LE can do some amazing things with heads also. Fastbird has a set of TFS heads ported by LE and they put mine to shame on the flow bench (granted my AFR's are 180's and his TFS heads were 227's)

Ryan Stout
10-15-2009, 06:46 AM
After pricing a few items, I have so far a Lunati sledgehammer crank, Scat forged H beam rods, SRP 31cc dished pistons, JE rings, and a set of 4 bolt splayed Eagle main caps (already on their way). How does that sound for now? A total of $1600 so far in parts, then about $500 in labor I've been quoted and $570 for a LE cam and Patriot extreme springs (as suggested by LE).

CALL911
10-15-2009, 08:05 AM
Sounds fine man.

Ryan Stout
10-15-2009, 09:59 PM
I'll be ordering some parts next week it looks like. BTW, while I have your attention, what size(s) are your wheels and what tires did you do with? I snatched up a set of OE C5 wheels a few months ago for $100 for all 4 (17x8.5 and 18x9.5). I'd like to get some DRs for the back. Thanks for all your help, I appreciate it. I'll use this as a build thread and get lots of pics in the next few months.

CALL911
10-16-2009, 09:26 AM
I have 18X9 up front and 18X10 in the rear (used to have 17X9.5 all way round). With DR's.