Real tech discussion on design, fabrication, testing, development of custom or adapted parts for Pontiac Fieros. Not questions about the power a CAI will give.
I would tell just about any kid in school that 10k that need not be squandered on a car shouldn't be.
product1620 wrote:
donk_316 wrote:
product1620 wrote:wow, im sorry I thought I was in tech, oh well. Yea don't spend your money on the fiero, cause fieros are teh suxxxors, you should spend it on something coool like a skyline or a supppra or an sti or hell anything import cause imports fucking OWN domestic econo boxes like our POS fieros. All hail the mighty import! only spend your money on imports!
BTW when this gets edited out please consider editing out all the other posts that have absofuckinglutely SHIT to do with the questions he asked. K thnx have a nice day! :thumbleft:
Im sensing... hostility towards imports...
No, but it seems that everyone is cool if you say im droping 15k on a skyline or 30k on an Evo, but if you say your putting some money into the fiero, its a different story; it suddenly turns into noooooo, save your money, invest in your future. He already said he was going to school, give the guy some credit, hes not dropping out of school to become a proffesional street racer. Its his money, let him do with it what he wants, this is TECH; he asked a tech question, not "what do yall think I should do with my money". I have no beef with imports at all; I just don't like the elitist mentality that comes with a lot of their owners.
He's only squandering 3k on the car. The other 7k is going for a bike witch in tern will save him mony on gas over the corse of 2-3 year's! that alone will save him in the long run well over 15-20k.. Thats a great investment :thumbleft: + he get's to spind some mony on making his idea's come to life.
I am not sure that the 3.4 ohv pistons couldn't be used as I dont' know if anyone has tried it. THe DOHC is n.ot an interference motor. Would putting these pistons in make it that way? Hard to say. I have no idea how close the current pistons come but with only .370 lift and not much duration, I doubt there is much to worry about.
I think it could be done. THe pistons sit down in the head a decent amount from the deck height. Not sure how much that is but I could prob find out in a week or so. Then the valve would have to be open a significant amount considering that the ohv pistons sit below the deck height. WHich means that hte valves would prob almost have to be near max lift or near max lift with the piston near TDC for there to be contact.
All it would take is like $35 and some free time to find out
FieroPhrek working on that ls4 swap for 18 years and counting now. 18 years!!!!! LOL
spend the $550 bucks and get (ROSS / JE / etc etc) custom forged set of pistons thats arent a hodge podge or modified other application.
Concur, but add CP to that list. They make teh awesome shiznit.
and buy proper new fuel injectors not someones used left over garbage.
Disagree. Unless you're making soooo much power that no production injectors can supply your engine, new injectors are a waste. Injectors pretty much don't wear out. They do get gummed after sitting for a while, but that's easy to fix.
Shaun41178(2) wrote:I am not sure that the 3.4 ohv pistons couldn't be used as I dont' know if anyone has tried it. THe DOHC is n.ot an interference motor. Would putting these pistons in make it that way? Hard to say. I have no idea how close the current pistons come but with only .370 lift and not much duration, I doubt there is much to worry about.
I think it could be done. THe pistons sit down in the head a decent amount from the deck height. Not sure how much that is but I could prob find out in a week or so. Then the valve would have to be open a significant amount considering that the ohv pistons sit below the deck height. WHich means that hte valves would prob almost have to be near max lift or near max lift with the piston near TDC for there to be contact.
All it would take is like $35 and some free time to find out
Huh? Does the OHV block have a different deck height? On the 91-95 DOHC motor the pistons protrude .011" ABOVE the deck surface.
The Dark Side of Will wrote:
Disagree. Unless you're making soooo much power that no production injectors can supply your engine, new injectors are a waste. Injectors pretty much don't wear out. They do get gummed after sitting for a while, but that's easy to fix.
Aye. There's seriously very little reason to get new injectors. A $60 trip to Cruzin Performance and they're good as new and even flowtested in case you think the flow rates might be wrong.
Series8217 wrote:
Huh? Does the OHV block have a different deck height? On the 91-95 DOHC motor the pistons protrude .011" ABOVE the deck surface.
I don't know. I wasn't able to find those specs on the 60 degree site. I think all the pushrod blocks deck heights were the same with it being 8.818 inches. All used the same type of stroke, same sized rods, and pistons didnt' change from year to year except with the different strokes and bores. AS in the Compression heights of the pistons were the same for all 2.8's iron or aluminum head.
Not sure if the DOHC block is different. I bet a machine shop would have the book with the specs in it. Or even a factory service manual for the luminas with that engine. Maybe even a Haynes will or chiltons.
AS far as I know all the pushrod pistons before the gen 3's all had the piston just below the deck height. Gen 3's have the piston poke up above the deck.
If its true the DOHC pistons stick up .011 above the deck, the 3.4 PR should be below the block, which would give plenty of clearence then I think.
FieroPhrek working on that ls4 swap for 18 years and counting now. 18 years!!!!! LOL
Shaun41178(2) wrote:
I don't know. I wasn't able to find those specs on the 60 degree site. I think all the pushrod blocks deck heights were the same with it being 8.818 inches.
AERA says 8.8190, so they're the same.. hmm..
Not sure if the DOHC block is different. I bet a machine shop would have the book with the specs in it.
Guess what I'm getting this info from.
If its true the DOHC pistons stick up .011 above the deck, the 3.4 PR should be below the block, which would give plenty of clearence then I think.
I just don't get how the 3.4 PR pistons are below the block when the DOHC pistons aren't.. they have the same compression height!
well if they have the same CH, and you do the math, then that should give you teh answer. I was always under the assumption that the pistons in the pushrods sat below the deck height. At least with the 2.8's and 3.1 but I could be wrong. Maybe it was changed with the 3.4's. Math doesnt' lie. This is all based on the iron heads.
I think I was told before that the fiero pistons are below the deck. I mean with a .040 crushed head gasket(again from what I have read but never verified), thats a tight ass quench you know? Too tight really. Maybe the 3.4's use a thciker gasket like the aluminum engines
What do the 2.8 and 3.1 iron head and aluminum head engines have for CH on their pistons? It is less then the 3.4 iron head? Well the 2.8 will prob be much different but the 3.1 and 3.4 is it much different?
FieroPhrek working on that ls4 swap for 18 years and counting now. 18 years!!!!! LOL
3.1 iron head and al head pistons have a 1.450 CH at least from SILV. Factory pistons might be different but just going by what this says.
Doing the math, with those CH, the piston sits at a height of 8.805. DH is at 8.818 so that means the piston with a blueprinted block sits .013 below the deck height.
DOHC pistons on that page have a CH of 1.457. SO a tad higher but still .006 below the deck.
The camaro piston has the same deck height so it would sit below the same amount of .006 below the deck height.
Now factor in the thickness of the gasket, and then how far the valve has to travel to actually make it into the cylinder itself, you can see that its most likely very possible that the 3.4 ohv pistons can be used in a dohc application.
FieroPhrek working on that ls4 swap for 18 years and counting now. 18 years!!!!! LOL
I might have some old DOHC head gaskets laying around in the garage still. I'll measure them for reference.
According to Silvolite specs the 3.1 PR piston has a compression height of 1.45". THe 3.4 has a CH of 1.457". That still puts the OHV piston above the deck.. hmm
Series8217 wrote:I might have some old DOHC head gaskets laying around in the garage still. I'll measure them for reference.
According to Silvolite specs the 3.1 PR piston has a compression height of 1.45". THe 3.4 has a CH of 1.457". That still puts the OHV piston above the deck.. hmm
I just did the math, it sits .006 below the deck.
The 3400 piston on the same second link is 1.470 which is .007 above the deck. THose are the only ones that stick up above the deck without decking the block.
FieroPhrek working on that ls4 swap for 18 years and counting now. 18 years!!!!! LOL
