Dyno tuned a 4.1 stock block today

[Otto J]

I tuned a 4.1 stock block with stock crank,rods,fgd pistons and girdle,Reed 224 roller cam,champion unported GN1s,champion intake,stock headers,Turbonetics 72BB,3" downpipe,precision front mount.
Made 588 RWHP at 28#s of boost on a 11.3 A/F

This is in a full weight stock car,So we will need a rent day to make passes as there is no bar in the car.

[sixgun86gn]

Cool,everybody says the 4.1 is too weak I think thats BS.

I had one with ported irons make 500rwhp at 20# with only a 218/218 flat tappet,t63,stock rockers,ported stock intake,70mm TB and plenum,PTE FMIC,with a T+ extender , and street chip and 83# injectors.No girdle or caps either.

Trans valvebody took a dump the first time I turned it up to 25#,went 127 in the 1/4 on just 20# though.

I think the 4.1 isn't given enough credit.

[SVT F15O]

Thanks for the great tuning Otto!!!
I can't wait to get it on the track and see what it can do.

[SPOOLN]

Yeah those 4.1 are not given enough credit.... Any block will come apart if its not tuned right.

[1QWIK6]

What was the torque?

[Ted A.]

Good job Otto.

[SVT F15O]

Originally Posted by 1QWIK6

What was the torque?

644

[GBGN1]

nice set up !makes me even more want to build one for my WE4.
Do you think that an eagle crank and girdle would have been a better choice??
thanks
Brian

[SVT F15O]

Originally Posted by GBGN1

nice set up !makes me even more want to build one for my WE4.
Do you think that an eagle crank and girdle would have been a better choice??
thanks
Brian

Over the winter I will probably do the Eagle crank and a good set of rods. I already have the girdle. Then it will be time to see just how fast a production 4.1L can go. I'm not worried, if it breaks, it breaks. -Mat-

[GBGN1]

You plan on useing any HARD BLOCK in the block-maybe lifter valley or??
Good luck
Keep us posted
Brian

[getchasum]

Nice Numbers

Kind of a tech question but since the post is showing intrest to the 4.1's I have a question.

The cat/eagle cranks out weigh the stocker by a few pounds, so question is.... if you'd used a forged crank with out a girdle or billet mains would the added weight stress the block more than a stock crank

If this is a hijack, sorry

[SPOOLN]

I would think the gurdle should hold it together.

[getchasum]

with out a girdle or billet mains would the added weight stress the block more than a stock crank

[CalgaryGN]

Are there any good 4.1's to look for ?? What cars had them and what casting numbers ?

[boostingbuick]

My 4.1l has gone 10.98 on pump gas. I see no reason to stay away. If you are planning to run a 4.1 then try to get an 84 block. Just drill and tap the front of the block to 1/2 npt and you can run a stock style drain.