Psi Questions

I finally decided to turbo my car and I got all the stuff (used) from a CATARPILLAR engine. The turbo is pretty big and I don't want to damage/destroy/freaking explode- my car.
Does anyone know how much boost a 95 DOCH V-Tech del Sol can take at a safe distance from exploding?

Also my car only goes fine until it hits 100mph then it doesn't budge from that speed. Is this due to a governor or is it because of my.. .my.. .my.. .um automatic transmission? What can I do to fix that speed problem?
Any suggestions are very much appreciated.

first of all, you don't have a DOHC VTEC del sol w/ an auto tranny, they didn't make them. i will assume you have an si model w/ the sohc vtec, so i wouldn't boost much more than 5-6 psi since it doesn't sound like you have anything else done to the motor.

[ShEaNy]

what turbo did u get? how big is it?....did u get a bOV, wastegate, Intercooler? what mods do u have done? u need more info here...

I'm not exactly sure what I was thinking when I wrote dohc, b/c it is a sohc. Sorry. All I have is Exhaust (skunk 2), Intake, and wires. I have everything for the turbo. Piping, intercooler, but i'm not sure what a wastegate is?

[delsolvtec]

Whatever you do don't boost more then 7psi on stock internals. I made that mistake and fried my pistons, blew my head gasket etc...

I went with arias low comp pistons
total seal rings
greddy 2mm head gasket
and a ton of other upgrades.

I now boost 10psi all day with no problems.

[KwikR6]

Originally posted by delsolvtec
Whatever you do don't boost more then 7psi on stock internals. I made that mistake and fried my pistons, blew my head gasket etc...

I went with arias low comp pistons
total seal rings
greddy 2mm head gasket
and a ton of other upgrades.

I now boost 10psi all day with no problems.

Listen to him

Thanks alot for the pointers, but I still don't know what a wastegate does. And about the governor???

Whatever you do don't boost more then 7psi on stock internals. I made that mistake and fried my pistons, blew my head gasket etc...

Was it dyno tuned???, thats probably why you fried them. i got a friend with a T4 on a 95 SOHC EX engine and hes running 12psi with no problem. He also has stock internals. last i saw him he had 242hp at the wheels, im going to see him soon again cause there putting on my turbo.

The turbo is pretty big and I don't want to damage/destroy/freaking explode- my car.

if the turbo is that big then i dont think it will work right with your car. if the turbo is big then it will spool up late, i just hope that your redline isnt before 7000rpm. since you metioned that it was BIG, it might not make any power at 8psi. a T4 only makes power when its set at 10psi and about, and at 10psi is about an easy 220hp.

if its the size of a T4 then its too big, T4's spool at about 4500rpm

Since you mentioned that you have an automatic just becareful cause automatics dont handle much power unless there built for it. So im going to say about 8-10psi (only if tuned!!)

did u get a bOV, wastegate, Intercooler?

he doesnt really need a BOV, maybe a Bypass valve from a 1st gen Eclipse. since the cars and automatic its not going to have much pressure to release cause the turbos always going to be spooled. Wastegate ya he could use one, Intercooler yes needed. one from an old Starion/Conquest would work. try E-bay

If i remember correctly a wastegate holds the psi at what its set at. EX- if you set it at 10psi the wastegate will wait till its at 10psi holds it there and lets the extra exhaust out thats trying to get it above 10psi. mostly so you dont get boost spike and blow your engine.

most people run the wastegate exhaust into the exhaust or out the side/under the car. BTW- they are very loud when when they exit out the side/under the car, but they sound GOOD.

[ChrisCantSkate]

^listen to him and delsolvtec they will point you in the right direction

[delsolvtec]

Yes it was dyno tuned. The single cam motors will not hold up for a prolonged period of time on stock internals with over 7psi of boost. Hondas come stock with extremely weak rods and pistons. The stock compression will cause way too much pressure under boost causing piston/rod failure. Trust me, I speak from experience. It's easier to do it right the first time.

Especially since the guy is new to installing a turbo on a naturally asperated car. I don't think he is going to shell out the money to dyno tune either.

Also make sure you upgrade your fuel system. The stock computer is going to throw your check engine light on as soon as the fuel pump, injectors etc.. can no longer keep up with the extra air the the turbo is feeding into the engine. You have to upgrade your fuel pump, injectors, fuel pressure regulator and possibly your ECU to compensate for boost.

I wouldn't suggest running a turbo off of a caterpillar. I'm assuming it's a turbo designed to run on a diesel engine. It's going to have massive ammounts of turbo lag. I would suggest saving your money and picking up a Greddy kit. Figure you are going to have to have a custom exhaust manifold made already, you might as well save your pennies for a few months and pick up the basic greddy kit for about 1500$. Just remember, do it right or don't do it at all.

If you have the means to build a one off turbo kit then by all means do. If you have limited knowledge of how turbos work and affect all other areas of an automobile then leave the kit fabrication to the pros.

Yes it was dyno tuned. The single cam motors will not hold up for a prolonged period of time on stock internals with over 7psi of boost

thats exactally what the owner of the car said, he said that you and other honda owners say that they cant hold over 7psi.

im just saying that if it was turned RIGHT then it will run over 7psi, he has had the turbo on the car for about6 months now and its always at 12psi. its also his daily driver, so im pretty sure that the car would have died by now if you say that it cant hold over 7psi.

he hasnt changed anything internally, just the modern things that you upgrade with a turbo (fuel pump, injectors.......)

It's easier to do it right the first time.

if you want him to do it right the first time then a dyno tuning would be the best thing. ya i know its pretty expensive, and so is a new engine. thats what hes looking at if not tuned, never go by a gauge. the best thing to do is get a kit like delsolvtec said, it is designed for the engine without much modifications. if something happend to the car im sure the people that designed the kit will pay for a new engine that is only if you hooked it all up right. if you know what your doing you can actually install it in your driveway.

ill get more info cause im going up there on Monday to pick up my car. ill get pics of the CRX also and the engine

Originally posted by Galtree
i'm not sure what a wastegate is?

Ur gonna want one, its very important for you if you dont want to blow up your car.

[pimpinprelude]

wait... its off of a caterpillar???? those turbos are huge!!!!!! and like the oher dude said, thay are going to have huge amounts of lag, and i would check how much psi it produces, probly a lot since the engines are so big. i would sell it and SAVE SOME $$ AND DO IT RITE! good luck!

[ShEaNy]

yea i wouldnt put that turbo on there....its prolly WAY to big...save up for a Greddy Kit....

[KwikR6]

Originally posted by pimpinprelude
AND DO IT RITE! good luck!